This is a special room. Then -- -- New York less than 72 hours after three people were killed and sixteen more injured by a gunman at Fort Hood Texas. Investigators are now working into the timeline of events and they believe can help explain why suspected killer Ivan Lopez opened fire as fellow soldiers. The very latest on the investigation from Fort Hood I want to bring an ABC's Mary -- and Texans Mary. Afternoon -- and while we're getting a window at stake into those moments of chaos here specialist Ivan Lopez and opened fire. Killing three of his around. -- -- -- -- -- -- -- -- currently aren't quite as good and -- portable area. The 911 calls came pouring in him. It was 4 PM on Wednesday an army specialist Ivan Lopez had opened fire on his fellow soldiers. Talk about it about it. -- Emergency responders rushed to the scene as Lopez continued shooting. Killing three wounding sixteen. There any sort of -- court for breast. Patient orders today and brought up -- but ran. Out of the chaos heroism. Lopez was confronted by a female military police officer. After she fired at him he put his gun to his head and pulled the trigger. Among the dead Sargent first class Danny Ferguson. His fiancee telling Florida station WT SP he gave his life to save others blocking -- door -- that wouldn't lock. Not being that want to -- normal again. -- -- -- -- -- -- -- -- Also among the dead Sargent Timothy Owens -- from her -- -- -- rendition of mine plan. -- is -- good person Lopez was tackling mental and emotional health issues he was last seen by a psychiatrist a month ago. But the Pentagon insists there were no warnings of the violence to come. No -- indication on the record of that examination that there was any sign of likely violence either to himself for two others. Now officials here believe that Ivan Lopez may have argued with another soldier before the shooting but they say there's no evidence. That he was targeting specific individuals and -- we just received a statement from Ivan Lopez's father. He says that his son must not -- been in the right mind that he wasn't like that. He also cites the fact that Lopez. Was undergoing medical treatment after the passing of his mother recently. And his grandfather and his father's as the recent changes when transferring to the -- surely may have affected his condition. -- that is the latest from the family but what do we know -- at this point about those other victims of sixteen people. In the hospital. Well there is some good news today we know at least five of the injured have been released from the hospital but got word this morning -- three have been upgraded from. Critical to fair condition but keep in mind these soldiers came into the hospital with severe injuries. -- -- several -- were shot in the head and neck and spinal injuries so this is going to be a long road of recovery van. -- stay with us from Fort Hood because -- wanna bring in ABC's -- Martinez is standing by at the Pentagon and Louis. There is now some suspicion that the shooting was set up possibly by an argument as Mary had just mentioned there with a fellow soldier what do we know about that potentially. Well actually again very little the information came -- from lieutenant general mark -- -- his news conference yesterday. Indicating that there was some kind of an argument between -- Lopez and a soldier or other soldiers. But they didn't have the specifics what they did know exactly did occur prior to the shootings having taken place on that same day the shootings. But very little information decides that an -- we are awaiting a news conference with Texas governor Rick Perry missed a short time from now. On the latest on the investigation there. Mary you've been on the ground outside of Fort Hood for a couple of days now how is that community dealing with all of the scrutiny of the army generals and -- in the political leaders. Going over the security detail and the precautions that may or may not have been take. This of course is a very resilient community remember this is the second time they have gone through. This kind of a situation in -- in five years -- it was just in 2009. When they suffered about that what was the deadliest -- -- current US military base ever in US history this is something they had dealt with before they understand. This kind of scrutiny but of course. This reopens in investigation. Really a lot of new calls today that we're hearing to reexamine. Its use of mental health and in the military and mental health and gun ownership much more broadly down. And we will -- -- -- that news conference when it does begin when the governor does make as we have to the podium that same right behind Mary there. But I want to bring a senior FBI agent and interrogator Brad Garrett -- conversation and Brad. You've had experience with dealing with these kinds of cases before have you seen anything so far in this investigation. Information it's been out by the military the might have suggested that Lopez was capable of something like this. No but I think the problem is that did mr. Lopez was very good at masking what he was really feeling. And if you look at many of the mass shooters we've dealt with in recent years. There's been a lot of overt signs. Erratic behavior irritability isolation. They've written about what they're about to do they've purchased firearms. Mr. Lopez that's -- profile I think all of those things probably we're going on with him. But he could sort of create a mask every day that everything was justified smile shake hands. Be nice to neighbors except for but inside he's actually boiling for whatever reason. And as those sixteen other victims are making their recovery in the hospital and mourning those lives that are lost the investigation is going on now. -- in this case obviously there -- no suspect to interrogate how -- the FBI begin then without that critical piece who speak with first what are you asking them. Well you have to draw a fairly large circle the obvious one are close -- and media people in the unit. The commander of the psychiatrist that have recently interviewed him this is current wife then you go to neighbors and you go to family. -- you -- have to go back several years I think your -- -- you're gonna have to go back to the Puerto Rican National Guard what went on in his life there. What happens with people like mr. Lopez is a life becomes one disappointment after another. In it deals and side and they don't they don't figure out any other way too little to alleviate. That rage and anger. And it just continues to build and so they get to a point where. I'm not gonna take it anymore and I'm going to inflict damage on those that are immediately -- around me that I think are contributing. To my downfall. And my guess is that's went. Motivated his shooting which I'm convinced was had been planned prior to -- -- curry he made out of picked yesterday exactly but -- a lot of fire recently. In -- launched I think -- using the argument. With a fellow soldier as an excuse. Lilly from what you've been hearing your perspective at the Pentagon there how are people in around. Reacting to something like this having dealt with this in 2009 having dealt with the -- -- charge -- shooting. Is it is it reflective of the system is their failure of the system what kind of evaluation is going. Well it's it's somewhat difficult to fault the system now the navy yard shootings a different story this he had such overt bizarre. Erratic behavior prior to the shooting so there was clearly a breakdown with him. So far we've not heard anything that would support the low -- Lopez fits that profile. But in -- -- were exhibiting behavior why. Alexis it at that the navy yard you really have to note. There's something going on with a person other than what's on the service. That's not really the job of people or even psychiatrists to pick to that level to figure out what's going on with -- so. Lopez. Is a very difficult -- with what we know so far -- have said for days ago this guy's going to be a -- shooter. -- where is the level of discussion now though on eyes as far as security at bases or at any kind of military facility either at home or around the world. In an and -- -- has been posted Defense Secretary Cagle has been traveling to Asia this week while all this has been going back here stateside. And he's been asked about this and he's talked about other changes that were implemented in 2009 after the shooting at Fort Hood. How the new changes are going to be implemented in the wake of the Washington -- you're cheating. And he said that will you know basically have let the investigators do their job here to determine what the facts were. What the motivations were what needs to be fixed because he's stressing that and -- obviously something has gone awry he said this -- several times. And he says he predicts that there will be no doubt the changes coming in the future. With regards to -- security. And no doubt with three with the focus on the insider threat. As we've been talking about force protection of military bases does a good job -- -- from an external threat. They've now got to reconfigure themselves and work on how to protect. Soldiers or other service members from. Others who may be -- have access to those bases. Mary you just read a statement from Lopez's father and and that's that the the family -- statement at this point that we haven't there. What about the people around Fort -- what are they saying about -- suspect. They remember him as a friendly guy one of his neighbors telling us that he was always smiling ghost stimulant really saw no red flags no warning signs. -- the -- that was to comment when we've seen of course those photos. Of love Lopez with his family to remind us of the husband and don't bother. When as Brad mentioned -- the psychiatrist didn't see any indication that there was violent streak to him he had no no previous record of violence. So all of these pieces coming together ever wanted to. Of course trying to comb through his background see what just happened to me Lopez snapped and the way he did of course it. Sought help for mental health issues he's -- -- evaluated for posttraumatic stress disorder but hadn't yet. Being diagnosed all of these pieces coming together but here in this community he was remembered as a good soldier and a friendly man. Brett and I -- I want to bring you back into this because again we're talking about the preventative measures that either may or may not have been in place or could've been implemented. It in your assessment as the military doing enough either have questions being asked about this given the fact that that as you pointed out that there are still very little known that's about Lopez at this point. And that from previous shootings there is are there are great deal of differences. But how I mean that that's a very special challenge and obviously for the military to to be able to prevent something like this in the future when there doesn't seem to be -- common thread. Doesn't seem to be -- common thread and you really have to rely. On reporting of those in and around in this case mr. Lopez in other words did fellow soldiers. Commanders. Anybody that surrounded noticed something -- did he -- at some point and and come out of this sort of mask being OK and then they see a side of him of -- where did that come from kind of thing. Again that's going to be people around him willing to -- to report that type of information. Problem with the military is the history from a historic -- -- don't even like talking about mental health issues so getting them to report that. Is a whole different a different problem. The physical security of this I'm not sure the military can do a whole lot about it. If you have 50000 plus people living in and out at Fort Hood -- on a daily basis. You can't set up metal detectors or check every car I -- this really boils Stanton can they do a better job of assessing. The people they have under their command. And there you know they're understaffed from a mental health standpoint. In so it's it's sort of like can we actually catch up. And the real answer is. I'm -- that you can stop the next mr. Lopez particularly based on the present profile we know him. -- lately we discussed this yesterday about that -- the possibility of trying to search everyone that's gonna make their way onto a military base and just how feasible that is or is not. And you know -- -- I'm gonna say -- bragging just hit right on the -- this was the same discussion that we had. With the Washington media are cheating and it's too many officials are saying that it's just unrealistic to expect you're going to have to you. They impose such strict security searches. At every military base and you were talking about large facility -- time out vast numbers of facilities. But you gonna spend a lot of resources to do this so how do you think how do you go about doing this what I -- -- tightened some restrictions but -- raising it to. Level. Mandatory searches might just be a -- too far. On the there's and I think the discussion back -- the meteor or shooting was you know what what do you do you -- do this at every movie theater you do this in the civilian relating to do this. At malls it would mean what how far you take something like this begin and end with -- -- do this occurrence scenario workplace shootings. It's up to something it's gonna have to be taking hard look at. But it's very detailed imagine that something as extreme as that and might be accepted. -- wanna get your thoughts on this and and Brad if you can weigh in after after Louis doesn't -- you don't hear from elected official expressing their desire. To keep firearms under the hands of mentally ill Ivan Lopez though at this point never received a formal diagnosis -- is it making it more difficult then for those that are trying to champion that kind of effort because we don't have that definitive label we can put on this suspect. They have to get two scenarios here you have. My community society that is trying to help those who -- suffering with mental health issues not trying to statement ties them. By saying that we're gonna label you this right off the bat. We want you seek care that you needed to saint Tanya the balance it. With a safety issue and -- have -- gun control advocates saying that maybe this is something. -- than that needs to be looked at part of the background checks knowledge that -- them more. More stringent review. Of the mental health issues that a person may have. So it -- there's a careful balance and used to be looked at here and I guess I know which way it Scania. -- your thoughts on that. Please share. -- I really think that you're not going to be -- change the system much as far as mental health reporting because. That can actually be you know box you don't -- -- open because just because somebody comes in. Maybe make some bizarre statements has depression may be has PD STE. That that's in goes into -- system -- -- can't purchase a firearm. And you know the present system. Has two problems one that the people have been adjudicated as mentally ill that was our records are not giving -- to state systems. And I think that's probably there's an under diagnosis there are people out there that probably should have been adjudicated by -- judge. As mentally ill and should not possess firearms to get into the system. The bottom line in from my view is this has to start small I think trying to attack the firearms side and it is is not -- could use a time. I think -- gonna have to start training people within their units within their schools within their companies. You've got to help us here we're not gonna go have somebody arrestor or fire -- if you come and tell us you've been noticing something purchase of firearms. You know making inappropriate comments about a boss and I'm not talking about one time I'm talking about a pattern. That's what has to come to the military. To law enforcement to whomever has -- system. So they can better assess. Who might be a potential shooter. Mary you you're standing by Fort Hood there where we are waiting in the latest news conference from the governor of Texas -- Rick Perry. But going back to the official account of what happened on the base during the shooting acts of terrorism as -- an act of heroism. They say -- so many lives to people there are they accepting everything they are hearing for the military or certain questions. As this investigation is still under way. Everyone I think here is is it. Taking at face value of the hearing from the military you mention of course those stories of heroism that are coming out in particular one sort of -- female military police officer. Who confronted the shooter directly. She fired at him and that was what made him reached inside his coat. Pull out his gun but -- his head and pulled the trigger we're also hearing -- story. -- -- military chaplain who helped save several other people and of course one sergeant who himself was injured. And his fiancee told us that he putting himself at risk to save others essentially. -- blocking -- door that was locked with his own body putting himself in harm's way to save others so. As always situations like this amidst all the tragedy there are these great stories of true American heroism. -- -- also wanted to ask you about Fort Hood itself obviously the basis largest very expansive at the same time the community relatively small. Are people -- being questioned about what they saw what good character background on Lopez. This is actually an ongoing investigation so officials are going through with a -- -- home talking to members. Of the community people that were there on the -- during the day. All of this still very much. Ongoing but keep in mind this is a tight knit community and this is something they have had experience with the before. Louis want to bring you back into this -- talking about a little bit of the background. Ivan Lopez. What at this point our investigators able to release about his mental state about any of those kinds could potentially confidential files whether they be psychiatric evaluations -- medical records. -- -- right and these are confidential files and there is the privacy act that provides limits. And how much information can be provided about an individual's mental state. Their health status things like that. So we have to go -- mainly on public statements from the senior officials have been talking about the case. -- we heard army secretary -- yesterday talk about how Lopez they had been receiving treatment for depression. Anxiety. And -- sleep disorder and so the heat said that he would receive some medications for that but the only one that he publicly disclose was ambient. So the question has to be what else could he have been receiving what other medications. Might keep -- he'd been under the influence. But that might be that they not that's too difficult to crack because of these privacy laws that are in place. And then also investigators looking at that what kind of individual he he is you know going back as far as they can talk to people who knew them. Martha Raddatz yesterday talk -- -- former sergeant. A when he was that the play to the Sinai back in 2007. That sergeant -- described Lopez as being an outstanding soldier. Somebody was exemplary and his conduct and that he was stunned. To hear the news that he was the man responsible for the shootings. -- how much then does that hamper investigators given the fact that some of the information can be made public and some cannot because. And as you well know there is obviously the trial in the public's -- -- what's going on right now in what happened in that tragedy -- two hours ago. It doesn't make it any easier for investigators when they have to deal with the privacy concerns of these this kind of information doesn't. And that's true now they will get access to it to mental health records that the public will not see at least four. -- -- a long period of time but you know the so goes back to. And you will actually even give you anything and other words the sort of the initial general -- is that the psychiatrist. Didn't really. Think he's that fit a sort of by a violent person profile if you will so. Unit of this case could have the potential to take a slightly different direction. The autopsy. Can they give them some information. City of some brain irregularities. Things of that nature since we don't seem to have at least on the surface. All of the -- that I would go through and other people would go through to assess. Potential dangerousness and somebody. So. In this this may have to -- directions other than we have than we have in the past traditionally gone with. National leaders all right. ABC's Brad Garrett and -- Martinez the Pentagon and gentlemen thank you both that was so they appreciate that and of course we'll be live streaming that news conference from Fort Hood. With Texas governor Rick Perry when he does make his way to the podium and of course you can stay up to date in real time on this story by downloading the ABC news app. And star in this story for updates on the go. For now though I'm down perhaps -- New York with this ABC news digital special report.

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